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Pinpoint Test AF: Abs (Anti-Lock Brake System) Module Communication Concern With The Pcm (Powertrain Control Module)

  1. Refer to Module Communications Network for schematic and connector information.

    Normal Operation and Fault Conditions 

    With the ignition ON, the PCM sends messages to the ABS module over the FD-CAN. If the ABS module does not receive these messages within the specified time frame, the ABS module sets Diagnostic Trouble Codes (DTCs). This can be due to a PCM failure, a circuit failure on the CAN or an excessive load on the network. For information on the messages sent to the ABS module by the PCM, REFER to: Anti-Lock Brake System (ABS) and Stability Control - Diesel/Flex Fuel - Ethanol/Full Hybrid Electric Vehicle (FHEV)/Gasoline - System Operation and Component Description .

    DTC Fault Trigger Conditions 

    DTC Description Fault Trigger Condition
    ABS U0100:00 Lost Communication With ECM/PCM 'A': No Sub Type Information This DTC sets when the ABS module does not receive any messages from the PCM within the allowed time.
    ABS U0401:86 Invalid Data Received from ECM/PCM A: Signal Invalid This DTC sets when the ABS module receives invalid data in the accelerator pedal message.
    ABS U0401:00 Invalid Data Received from ECM/PCM A: No Sub Type Information This DTC sets if the information in one or more messages from the PCM contains invalid or out of range information.
    ABS U0401:64 Invalid Data Received from ECM/PCM A: Signal Plausibility Failure Sets if the information in one or more messages from the PCM contains invalid or out of range information.
    ABS U0402:86 Invalid Data Received from TCM: Signal Invalid Sets if the information in one or more messages from the PCM contains invalid or out of range information.

    Possible Causes 

    • Network communication concern
    • Wiring, terminals or connectors
    • PCM
    • ABS module

  2. AF1 CHECK THE PCM (POWERTRAIN CONTROL MODULE) COMMUNICATION

    • Ignition ON.

    • Using a diagnostic scan tool, retrieve the DTC s from all modules.

    Does the PCM pass the Network Test? 

    Yes  GO to  AF2
    No  DIAGNOSE the PCM does not communicate with the diagnostic scan tool. REFER to: Controller Area Network (CAN) Module Communications Network - Electric .

  3. AF2 CHECK FOR PCM (POWERTRAIN CONTROL MODULE) DIAGNOSTIC TROUBLE CODES (DTCS)

    • Ignition ON.

    • Using a diagnostic scan tool, carry out the PCM KOEO self-test.

    Are any PCM DTC s present? 

    Yes  DIAGNOSE the PCM DTC s. REFER to: Electronic Engine Controls 2.7L EcoBoost . REFER to: Electronic Engine Controls 3.5L EcoBoost . REFER to: Electronic Engine Controls 5.0L 32V Ti-VCT . REFER to: Electronic Engine Controls 3.5L V6 PowerBoost
    No  GO to  AF3

  4. AF3 CHECK THE ABS (ANTI-LOCK BRAKE SYSTEM) FOR THE LOST COMMUNICATION DIAGNOSTIC TROUBLE CODE (DTC)

    NOTE: When retrieving DTC s, ignore all historical or CM DTC s.

    • Using a diagnostic scan tool, clear the ABS module DTC s.

    • Put the ABS module in sleep mode by performing the following steps:

      • With ALL doors closed, set the ignition from ON to OFF.
      • Disconnect the diagnostic scan tool.
      • Open the door, exit the vehicle and close the door.
      • Wait a minimum of 90 seconds for the ABS module to enter sleep mode.

    • Ignition ON.

    • Using a diagnostic scan tool, carry out the ABS self-test.

    Are any DTC s from the DTC Fault Trigger Conditions Table present and active in the ABS module? 

    Yes  GO to  AF4
    No  The system is operating correctly at this time. The DTC may have been set due to high network traffic or an intermittent fault condition

  5. AF4 REVIEW THE ABS (ANTI-LOCK BRAKE SYSTEM) MODULE SELF-TEST FOR VOLTAGE-RELATED DTC (DIAGNOSTIC TROUBLE CODE) S

    • Using a diagnostic scan tool, review the recorded DTC s from the ABS self-test.

    Is DTC U3003:16 or U3003:17 present? 

    Yes  For DTC U3003:16, GO to Pinpoint Test A  For DTC U3003:17, GO to Pinpoint Test F 
    No  GO to  AF5

  6. AF5 CHECK FOR PCM (POWERTRAIN CONTROL MODULE) DTC (DIAGNOSTIC TROUBLE CODE) S

    • Using a diagnostic scan tool, carry out the PCM KOEO self-test.

    Are any DTC s present? 

    Yes  DIAGNOSE the PCM DTC s. REFER to: Electronic Engine Controls 2.7L EcoBoost . REFER to: Electronic Engine Controls 3.5L EcoBoost . REFER to: Electronic Engine Controls 5.0L 32V Ti-VCT . REFER to: Electronic Engine Controls 3.5L V6 PowerBoost
    No  GO to  AF6

  7. AF6 CHECK FOR OTHER CAUSES OF COMMUNICATION NETWORK CONCERN

    NOTE: If new modules were installed prior to the DTC being set, the module configuration can be incorrectly set during the PMI or the PMI may not have been carried out.

    • Check the vehicle service history for recent service actions related to the PCM or the ABS module. If recent service history is found:

      • Verify the correct replacement module was installed. HVBOM may be used to verify correct part fitment.
      • Verify the configuration of replacement module was correct. Re-configure the module using as-built data if prior configuration is suspect.
      • Verify the module was not obtained from a like vehicle and installed into customer vehicle. Return the swapped module to source vehicle and obtain new replacement module.

    • Operate the system and determine if the observable symptom is still present.

    Is the observable symptom still present? 

    Yes  GO to  AF7
    No  The system is operating correctly at this time. The concern may have been due to incorrect parts replacement procedures or incorrect module configuration.

  8. AF7 CHECK FOR COMMUNICATION DTC (DIAGNOSTIC TROUBLE CODE) S SET IN OTHER MODULES

    • Using a diagnostic scan tool, retrieve the DTC s from all modules.

    Is any DTC from the fault trigger table set in 1 or more modules in addition to the ABS module? 

    Yes  GO to  AF8
    No  GO to  AF9

  9. AF8 CHECK FOR CORRECT PCM (POWERTRAIN CONTROL MODULE) MODULE OPERATION

    • Put the ABS module in sleep mode by performing the following steps:

      • With ALL doors closed, set the ignition from ON to OFF.
      • Disconnect the diagnostic scan tool.
      • Open the door, exit the vehicle and close the door.
      • Wait a minimum of 90 seconds for the ABS module to enter sleep mode.

    • Disconnect ABS module connector C135, if not previously disconnected.

    • Disconnect PCM B connector if not previously disconnected.

    • Disconnect PCM E connector if not previously disconnected.

    • Disconnect GWM connector C2431A, if not previously disconnected.

    • Disconnect GWM connector C2431C, if not previously disconnected.

    • Using a good light source, inspect all disconnected electrical connectors for the following:

      • Corrosion - INSTALL new connector or terminal and clean the module pins
      • Damaged or bent pins - INSTALL new terminals or pins
      • Pushed-out pins - INSTALL new pins as necessary
      • Spread terminals - INSTALL new terminals as necessary

    • Connect GWM connector C2431C. Make sure the connector seats and latches correctly.

    • Connect GWM connector C2431A. Make sure the connector seats and latches correctly.

    • Connect PCM E connector. Make sure the connector seats and latches correctly.

    • Connect PCM B connector. Make sure the connector seats and latches correctly.

    • Connect ABS module connector C135. Make sure the connector seats and latches correctly.

    • Operate the system and determine if the concern is still present.

    Is the concern still present? 

    Yes  CHECK OASIS for any service articles: TSB, GSB, SSM or FSA. If a service article exists for this concern, DISCONTINUE this test and FOLLOW the service article instructions. If no service article exists for this concern,
    INSTALL a new Powertrain Control Module (PCM). REFER to: Powertrain Control Module (PCM) 2.7L EcoBoost . REFER to: Powertrain Control Module (PCM) 3.5L EcoBoost . REFER to: Powertrain Control Module (PCM) 5.0L 32V Ti-VCT . REFER to: Powertrain Control Module (PCM) 3.5L V6 PowerBoost
    RVC: Generate RVC only works in single-step view Generate RVC requires VIN entry  .
    No  The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. ADDRESS the root cause of any connector or pin issues.

  10. AF9 CHECK FOR CORRECT ABS (ANTI-LOCK BRAKE SYSTEM) MODULE OPERATION

    • Ignition OFF.

    • Disconnect ABS module C135, if not previously disconnected.

    • Using a good light source, inspect all disconnected electrical connectors for the following:

      • Corrosion - INSTALL new connector or terminal and clean the module pins
      • Damaged or bent pins - INSTALL new terminals or pins
      • Pushed-out pins - INSTALL new pins as necessary
      • Spread terminals - INSTALL new terminals as necessary

    • Connect the ABS module connector. Make sure it seats and latches correctly.

    • Operate the system and determine if the concern is still present.

    Is the concern still present? 

    Yes  CHECK OASIS for any service articles: TSB, GSB, SSM or FSA. If a service article exists for this concern, DISCONTINUE this test and FOLLOW the service article instructions. If no service articles address this concern, INSTALL a new EBB. REFER to: Electric Brake Booster (EBB)
    ORDER a replacement ABS module and INCLUDE the RVC on the form. If this is a Ford paid REPAIR, INCLUDE the RVC on the warranty claim form.
    No  The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. ADDRESS the root cause of any connector or pin issues.
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